A lot of people make the easy comparison of Bret/Diesel to Bryan/Reigns. Could it be that we look back some day and see this more as a case of the Graham/Backlund decision?

No, because Graham was a major drawing card and was legitimately robbed of a long title reign that he deserved.  I think the Bret comparison is more apt for Bryan because he's not the guy who is gonna light business on fire or replace Steve Austin, but he's the placeholder guy who can keep business stable while they FIND the next guy.  I don't think anyone is seriously suggesting that Daniel Bryan was going to trigger the next boom period.  But was he a better choice in the short-term than Reigns?  Yeah, of course.